Machine to machine (M2M) refers to all techniques and means for connecting machines. The theory of M2M has appeared in the 90s of last century, but was still theoretical. Since 2000, with the development of the mobile communication technology, the networking of a machine with the mobile communication technology has become possible. M2M service has appeared in the market in about 2002, and developed rapidly in the next few years and becomes the focus of various communication device suppliers and telecommunication operators. At present, the amount of machines in the throughout the globe is much larger than that of people, so the M2M technology is quite prospective in market.
Research on the scenario of M2M communication application shows that providing M2M communication over a mobile network has a great potential market. However many new requirements have been proposed for M2M services, and in order to enhance the competitiveness of the mobile network, it is necessary to optimize the existing mobile network to more effectively support M2M communication.
The existing mobile communication network is mainly designed for man-to-man communication, and is not sufficiently optimized for machine-to-machine and man-to-machine communication. In addition, it is also a key to the success of M2M communication deployment that an operator can provide M2M communication services with a low cost.
Based on the above-mentioned situation, it is necessary to study the solution for the mobile network to support M2M communication; and the solution will reuse the existing network to a maximum limit, and reduces the influence on the network by large amount of M2M communication and the complexity of operation and maintenance.
The competition in the current telecommunication market is more and more fierce, and the tariff continuously decreasing; and the human based communication market is tending to be saturated, and M2M is a brand new development opportunity to the operator.
In order to effectively use the mobile network resource, the 3rd generation partnership project (3GPP) has proposed a machine type communication (MTC), i.e. a service of communication from machine to machine, machine to man, the range of service thereof goes far beyond the previous communication of Human to Human (H2H, and MTC differs from the existing H2H communication mode a lot in aspects such as access control, charging, security, Quality of Service (QoS), service mode, etc.
In the architecture of a 3GPP evolved packet system (EPS), the EPS includes a radio access network and a core network. The radio access network may be, for example, a UMTS radio access network (universal terrestrial radio access network, UTRAN), an evolved UTRAN (E-UTRAN), or a GSM/EDGE radio access network (GERAN). As regards the core network, for example, in an evolved packet core network (EPC), there are network elements including a mobile management entity (MME), a serving gateway, and a packet data network (PDN) gateway (PGW); in a GPRS core network, network elements such as a serving GPRS support node (SGSN) are included; and in an E-UTRAN, evolved Node Bs (eNBs) are included.
MTC device trigger is one of the basic requirements for MTC systems. In order to control the communications of an MTC device, the means of an MTC server initiating a poll may be used for communications. As regards the communications initiated by the MTC device, sometimes data also needs to be polled by the MTC server from the MTC device. If the query initiated by the MTC server returns failure or the IP address of the MTC device is unavailable, then the MTC server may use MTC device trigger to establish communication with the MTC device. If a network cannot trigger the MTC device, then the network reports an MTC device trigger failure to the MTC server. The MTC device trigger is implemented in 3GPP by means of control plane signalling.
The MTC device trigger includes mobile originated (MO) and mobile terminating (MT) services, i.e. including the MTC device sending or receiving information.
In order to implement effective transmission of an MTC device trigger request, the proposed schemes include: sending MTC device triggering information by means of a short message service (SMS), or sending MTC device triggering information by means of control plane signalling. With regard to the means of sending the MTC device triggering information by means of control plane signalling, the MTC server sends control plane signalling containing the MTC device triggering information to a network node, and the network node parses the MTC device triggering information in the control plane signalling, and then sends the MTC device triggering information to a user equipment (UE).
FIG. 1 is a schematic diagram showing the MTC architecture in 3GPP according to related art. As shown in FIG. 1, at the user plane, an MTC application device (Application) connected with an MTC user is in communication with an MTC server via an API interface, or is in direct communication with a gateway GPRS support node (GGSN)/PGW in a 3GPP network via a Gi/SGi interface. The MTC server is in communication with the GGSN/PGW via a Gi/SGi interface. The GGSN/PGW is in communication with a UE via a radio access network (RAN). At the control plane, the MTC server sends control plane signalling containing MTC device triggering information to an MTC interworking function (MTC-IWF) via a Tsp interface, or an SME sends control plane signalling containing MTC device triggering information to a short message service-service centre (SMS-SC)/IP-short-message-gateway (IP-SM-GW) via a Tsms interface. The MTC-IWF sends, via T5, the triggering information to an MME/SGSN/MSC, which then sends the triggering information to the UE; or the MTC-IWF sends, via T4, the triggering information to the SMS-SC, which then sends the triggering information to the UE.
FIG. 2 is a schematic diagram showing an MTC-IWF sending control plane signalling containing MTC device triggering information via a T4 interface according to related art. As shown in FIG. 2, the MTC-IWF directly sends an SMS containing the MTC device triggering information to an SMS-SC via a T4 interface to transmit the MTC device triggering information, and the SMS-SC finally sends the SMS to a UE. The UE sends an acknowledgement message to an MTC server via a network node; and if the trigger is successful, the UE establishes a connection with the MTC server for communication. In order to distinguish SMS triggering information from common SMS information, an SMS application port ID 49152 is utilized to indicate the SMS triggering information, i.e. after the MTC-IWF has received MTC triggering information from an SCS, the MTC-IWF adds a port ID 49152 to the triggering information to indicate the SMS triggering information, and sends the SMS triggering information to a target UE by means of a T4 flow. The target UE judges that the received short message is triggering information according to the ID 49152 in the SMS, and forwards the SMS triggering information to a corresponding application for processing.
At present, in the MTC triggering information flow in 3GPP, at least the following problems exist: if there are a plurality of different application servers (ASs) sending triggering information, the UE cannot identify the corresponding application and forward the triggering information to the corresponding application for processing according to the existing scheme; and when there is triggering information for non-MTC application, the UE likewise cannot identify an application corresponding to the short message triggering information according to the existing scheme, and therefore the requirement of sending MTC device triggering information to a correct application for processing cannot be met.